


Play By The Book

by hellhoundsprey



Series: ficlet prompts [24]
Category: Supernatural
Genre: Age Difference, Age Swap, Bottom Dean Winchester, Crossdressing, Daddy Kink, Dirty Talk, Discovery Kink, Feminization, Horny Teenagers, Incest Kink, Kink Negotiation, M/M, Sexual Roleplay, Top Sam Winchester, Unsafe Sex, Verbal Humiliation, pre-discussed consent
Language: English
Status: Completed
Published: 2020-06-26
Updated: 2020-06-26
Packaged: 2021-03-04 02:27:46
Rating: Explicit
Warnings: Underage
Chapters: 1
Words: 2,822
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24926149
Author URL: https://archiveofourown.org/users/hellhoundsprey/pseuds/hellhoundsprey
Summary: Prompt: wincest + feminization (fem dean) daddy kink, impregnation kink ✨
Relationships: Dean Winchester/Sam Winchester
Series: ficlet prompts [24]
Series URL: https://archiveofourown.org/series/478657
Comments: 7
Kudos: 191





	Play By The Book

**Author's Note:**

> Catch me vibrating out of my goddamn soul for this one, hfs anon.
> 
> Dean is 15, Sam is 19.

“Can we, uh. Do the…thing?”

Sam looks at him as if he doesn’t exactly know what Dean means. Grins and teases, “The _thing_?” and Dean is _this_ close to either punching him in the face or, worse—leaving.

He snaps, “Sam!”, all accusation, and his brother laughs at him as he pets his flanks.

Rubs his hands down to cup Dean’s ass over his jeans, rocks him in his lap ever-so-subtle.

“Yeah? Now?” hums Sam, sincere and at least as excited as Dean, and that makes everything a little easier. Kind of.

Dean nods and can _feel_ how red his own face is.

Sam laughs again—weaker, through his teeth.

Murmurs, “Fuck,” and, “Yeah. Yeah, you wanna go get it?”

Dean’s answer is swinging his leg over and climbing off both Sam and the bed. He bends down to fish for his duffle by the side of his bed, one hand on the wall for support. Daisy wallpaper, anno 1973.

His fingers easily recognize it by texture—so different from the plethora of worn-down cotton t-shirts, underwear, coarse denim jeans.

Smoother? Silkier?

By default, everything for girls seems to be that much more _tender_.

Belt and baggy jeans get discarded, exchanged for lavender pleats.

He can’t _not_ check back with Sam, Sam’s expression, Sam’s approval—and finds his brother smiling at him; gently, encouraging. Not exactly leering, but nothing’s quite ‘exact’ about them anyway.

Hears, “C’mere,” and Sam pats his thigh, and Dean swears how even from over here, he can see that semi going all the fucking way.

He untucks his tee as he walks, smoothens it down over his lanky torso, the belly with the hordes of butterflies in it.

Dean’s palms are damp and his skin feels way too tight.

Everything about all of this is still so fucking new.

Sam’s hunger shows in his hands. In reaching out and pulling Dean in even as he clearly already does as he’s told. In the reverent hum, the roam of too-big palms from Dean’s shoulder blades down his back, over the five-finger-discount skirt.

Dean’s got his lower back arched and his hands on Sam’s tits for support as they kiss. As Sam touches his fill, up-down and barely bunching up the fabric he’s so gentle about it.

Dean’s hovering on his knees because god, the sensation of being so fucking bare, of air licking at the inside of his thighs, his ass, his everything.

The skirt barely even makes it mid-thigh on him.

“Fuck, you look so hot.”

Hopeful, “Yeah?” and Sam’s delirious, “Yeah,” and Dean smiles against that cheek, arms around his brother’s neck now and holding on, keeping them out of the way. Closes his eyes and lets the goosebumps come and go.

Sam’s fingertips explore naked patches of skin, avoid blatant places like the constant drip of Dean’s dick, the peach fuzz on his balls, his taint. His gash.

“You even put underwear on at all, today?”

Dean chuckles his decline and his heart rabbit-thuds in his chest for Sam’s pained, guttural groan.

For that mouth on the side of his neck, slurred, “Fuck,” and, “you little slut,” and Sam grabbing one handful of ass like he owns it.

Which ain’t far from the truth at this point, but they’re both too chicken to make a big deal out of it.

Dean doesn’t think he could handle it.

Murmurs, “Not a slut,” with his eyes closed, arms tight around his brother; with Sam’s scent surrounding him, filling him.

“Sitting in my lap with your ass out like that? Sounds like a slut to me.”

Dean argues, “No,” and eases up on the one-sided hug to allow Sam’s not-on-his-ass hand to slip up his tee, pluck at the hard cherry-points of his nipples.

“Bet you’re as easy as you look,” murmurs the idiot who needed like ten hours of convincing that yeah, Sam, I want this, it’s fine, I’m into it, and still needed to have his hand held after they did it that first time one week ago.

“Bet you’d let your big brother get his dick up this pussy.”

Sam’s fingers slip to spread Dean’s ass to the open air of the otherwise empty room, and Dean nearly swallows his tongue.

Sam’s such a people pleaser.

“Uh-huh.”

“Yeah?” Sam laughs, play-pretend cruel. Took him a moment to get into character last time, too.

Dean cheats, “Only you,” and feels choked-up with it already.

Trembles with the heavy pause, with the increasing heat radiating from his giant brother, buried and pinned underneath himself all docile like he’s not totally capable of throwing Dean across the room if he tried.

Two hands on Dean’s ass, now; one holding him open, the other love-rubbing middle and ring straight over his hole, no preamble, no shame.

Dean’s ignored cock drools another clear line of precome over Sam’s perfectly flat stomach. Over Motörhead and fading colors.

“You’re so sweet,” hears Dean; sighed, low. Sam doesn’t suck love-bites into his neck (knows better, discreet places), but rubs his mouth there like he doesn’t want to care. “So sweet I wanna fuck your ass until you cry.”

Dean groans, “Fuck,” and tries his best to arch his back even deeper, offer himself better to those fingers.

Sam mumbles, “Yeah? You want that?” and it’s genuine and Dean has to assure, “Yeah, fuck,” before Sam finally growls like he’s letting himself go.

“Fuck, _baby_.”

Dean kisses that stupid mouth. In terms of embarrassment, Sam waxing poetry never fails to top parading around in girl clothes.

“God,” muffled between smacks of lips, hands still rough-housing Dean’s ass, “you sure? Please tell me you’re sure.”

Dean repeats, “ _Yeah_ , Sam,” sharper and he would be annoyed if Sam wasn’t basically dry-fingering him despite his verbal worries.

It had hurt a little, sure, but not that bad.

Dean can take a lot. Sam out of all people should have gotten that goddamn memo.

Testing, “Don’t you wanna?” and Sam gasps immediately, “Of course I want to, fuck, just—”

“Jesus, I’m not gonna _break_.” Unnecessary, “It’s not _that_ big,” and his grown-ass brother makes a puppy noise at that.

Finds his eyes, dark and stormy and Dean loves that little, secret smirk. Just for him.

“Big enough to make you cry on it.”

Dean tries, “I wasn’t,” but his eyes go slightly dewy with just the slow precision Sam works his own belt and jeans open with between their bodies.

Dean knows he’s pretty when he pouts.

Doesn’t know what kinda face he makes, though, upon the heat and smell of Sam’s bare cock reaching him, but judging by the sharpening grin on Sam’s face, it can’t be too disappointing.

Sam shimmies his jeans down his ass; just far enough. Grabs and works himself, judging by the sounds, and Dean’s nuts pull tight in sympathy.

“Bet you’re so fucking tight.”

Dean hums. Would have lowered himself any second now if Sam hadn’t already put one hand back on his ass, forced him down those two inches to let the ever-wet head of his cock pillow nice against the dry folds of his asshole.

Rubs himself, there, and kisses at Dean’s bared, goosebumped throat.

“Don’t have any condoms, though.”

Jesus. “Sam…”

“I’ll try and remember to pull out, yeah?”

Dean slurs blasphemies. Buries his face in the crook of that solid neck and humps back at his brother’s cock like he wouldn’t die taking that fucking monster dry.

Sam’s never a dick about it being huge, and that makes it so much worse, somehow.

“So fucking horny for it, aren’t you? Good fucking girl.”

Sam’s hand connects and Dean yelps. Holds on tight and gets another for how nice he curls his ass out for it—another, another.

Again, Sam curses, “Fuck,” before he manages to dig around in his own bag for the grimy bottle of lube.

Nearly empty, yet again, and Dean’s getting fucking weak-kneed at the sight of the packaging alone at this point.

Sam’s so fucking efficient about everything; got one and then two fingers up Dean’s ass to the knuckles before Dean can even take one true, entire breath. Dean gasps, shaken, for the burn, the violence.

They haven’t gone this far again ever since then. Not with Dean being sore as fuck and time not being kind, and then with Dad being nervous and paranoid and scribbling notebook after notebook all night.

It’s safe to say they’ve both got the bluest of balls.

Sam groans, “Fuck,” and yeah, Dean can relate. Mouth-to-mouth, teeth. “Like you’ve never taken _anything_.”

Dean makes a girl-noise. Hides his face again and Sam chews on his earlobe in retaliation, pulls at it and it hurts and he’s gonna make a fucking mess of both the skirt and Sam’s tee with how wet his cock is.

Sam’s fingers crook and bang him out where it counts, and Dean’s already, profusely, sweating.

“Gonna make it fit, though. Said I could, didn’t you?”

Dean sobs, “Yes,” under another smack to his ass, a third finger angling and forcing his hole too-wide.

Sam’s got slender fingers, but they’re long.

And even him being skinny all over doesn’t mean he’s not comically, unnecessarily _big_.

They’ve won different corners of the same genetic lottery, and it’s not entirely fair.

“Fuck, I’m just gonna use you up.” Dean nods, all scarlet; lets Sam scissor his fingers wide and wider and pull him open as he likes, lets him do _whatever he wants_ because that’s how this works. How Sam made him say it out loud and nearly die from humiliation that night, halfway under the covers, frantic hands on each other’s dicks.

“Put it in…”

“What was that?”

“Put your _dick_ in me,” blurts Dean, and how can Sam even be this smug with his tongue lapping at Dean’s sweaty throat?

Dean’s brain devolves by the second. By the rub and push of Sam’s cock up against his still-too-tight rim, the knuckles of his own hand.

Sam prompts, “Put it where, baby?” and Dean’s gonna die.

He’s just gonna perish. “I-in my pussy, Daddy?” and he didn’t mean for his voice to raise at the end, didn’t mean for it to break, croak like he’s been sucking dick for the better part of today, like he’s been screaming himself hoarse on it already.

“Hm.”

Dean yelps for Sam’s teeth. Hitches his hips for the slick heat of that cock, fucking demanding and nearly breaching him despite Sam’s fucking fingers still hooked up in there.

God, he’s gonna do it, isn’t he?

“Here?”

“Yes,” and again, “ _yes_ ,” shivering around the last one and Sam’s biting at his chin, now, while he fingers the fat head of his cock inside like he truly doesn’t care.

Like he’s not half a second away from breaking character, gasping for _is this really okay?_ and Dean’s gonna fucking _come apart_ on this.

“Please, _please_ —”

Sam donates one hand to Dean’s face, to turn and hold it for kisses and as he pulls his fingers back, he drives his hips up—all slow, all too-much, and Dean pushes down, and it works out like that.

One hand on Dean’s ass, eventually, when Sam can’t push much higher and Dean doesn’t sink down fast enough. Deep enough.

They grind, labored panting and drip-wet kisses. Both of Sam’s hands in Dean’s hair at some point, just stroking and loving and Dean groans an almost-human noise. Shifts his hips a little; up-down. Inch by inch.

“You’re aware you’re gonna take it all the way, right?”

Pleasure-slurred, “Uh-huh,” brother-fingers on Dean’s nipples again, milking him as a distraction, a there-there.

Sam’s bathed in sweat. “Fuck, you’re so tiny—everywhere.”

Dean whines. Tries his best, and Sam’s so so fucking hard, so fucking pulsing and fat in his ass. Every bump of a vein feels like too much.

“C’mon, at least try.”

Dean does. Bites his lip and lets Sam pull his tee off him, duck in and suck at his tits and it’s Dean’s turn to hold onto some hair, now. Rocks, blindly, and there’s the distant tickle of a pube or two.

Oh, lord.

“Let me in, baby, c’mon,” and Sam’s patience has reached its limits apparently, because his movements are picking back up. Drive him so deep Dean thinks he can feel him digging into his stomach, can feel himself pulling inside-out when he comes up; the strict pinch of Sam’s fingers as he grabs at one globe of ass again, uses it as a lever to pull, spread, make it work.

Mouth-whispered, “Can you tell how fucking wet it is for you?” and Dean’s gonna cry.

Nods, because, yeah.

“Not as wet as this fucking pussy, though.”

Pained groan, and Dean nearly topples over at two hands on his hips, Sam doing most of the work.

Dean’s low enough that his balls dip over Sam’s cut abs, that his sloppy, bare dick rubs itself stupid between skirt fabric and 80s cotton.

Mumbled, “So full,” and Sam hums in approval, harmony.

Pulls him lower and directs him up and down with the grip he’s got on him, opens him up with nothing but persistence and pressure and hastily added lube.

The bed begins to croak. Whisper-beginnings.

Dean slurs around every syllable of, “Fuck me,” and the first true thrust nearly sends him over the edge and beyond.

Trembled, “Fuck,” and Sam is quiet, bite-eats at Dean’s mouth, his lip, and rearranges his own ass on the bed, plants his feet more secure in blind search of better leverage.

They always escalate so fast.

Dean’s all hollow sounds; slap of skin on skin and pain and heat.

The next time they come close to ‘slowing down’, they’re chest to chest, flat on the bed.

He finds his brother’s sweat-shiny face, the blissed gloss of his eyes.

Hears, “Gimme a second.”

They’re both new at this and if the roles were reversed, Dean would have come his brains out ten seconds in.

He’s not mad.

Cheek on that shoulder, baby-rocks of his body—mainly Sam’s handiwork.

Pluck of fingers for the (most definitely) ruined skirt. Dean shivers with the tickle of fabric up his ass, doesn’t fight getting bared to the room with the bed facing the door.

God, if Dad busted through that door right now…

“Wish I could see,” coos Sam. Both hands on Dean’s bare ass again, spreading his cheeks and working his own hips, and the added stretch is fucking _good_.

“Need one of those rooms with mirrors on the ceiling,” agrees Dean, weak-throated but dark enough for Sam to hum like he’s right, like there’s nothing else.

“Fuck.” Kisses. “God, I want that.”

Those fingers inch inwards until they can rub around the wet clench of Dean’s ass around Sam’s cock. Where they’re connected and so fucking heated, and it shouldn’t be.

“God.” More kisses. “Bet you’re so pink here.”

Dean reminds, “You know,” and Sam love-groans.

“Yeah. Yeah, I do.”

So (too) easy to pick up where they left off—from grinding back to Sam’s balls smacking up against Dean’s ass in too little time. Sam’s fingers are still down there, pulling him wide to accommodate all that girth.

All Dean has to whimper is, “Sam,” and he gets what he wants.

One of those giant paws squishes between their bodies, finds his cock and fuck he’s hard, too hard; and Sam barely has to jerk him once, twice, under the incessant pump of cock against Dean’s insides.

Dean’s entire body groans with release, whips him like a dog—clenches him neck-down and god he can feel himself milking out his brother.

Unfailingly, “Fuck,” teeth-sharp and choked up and Dean yelps with how suddenly Sam rolls them over; has his big brother over himself now, buried—Sam’s press-holding the backs of his knees and pounds into him like they’re not human anymore, like there’s nothing, nothing, nothing.

A mere few seconds like this and Sam shakes apart, balls-deep.

Dean gulps for air, so fucking highly aware of Sam pumping his load up his ass.

Sobs, “ _Fuck_ ,” and gets his cheek bitten, his ear.

Curls his arms and legs around his brother who doesn’t seem to be able to stop grinding into him. Whose cock is still flexing, too-deep, still dripping.

Dean whimpers.

Sam pants, “Oops,” without a lick of empathy. “My bad.”

Dean’s slippery hands fist into the back of Sam’s tee under the again-growing rhythm.

Sam’s not going soft inside of him.

“Feels so good, baby girl. Couldn’t stop myself,” and Dean hears that smirk as he makes more kitten-noises.

Lets Sam work his load up his guts deep and deeper, and he truly feels bloated with it. As if…

Sam fucks him in long, even strokes.

Looks down at him like Dean hung the moon, personally, and rubs one thumb along his still-baby-fat cheek.

“Guess it doesn’t matter now, does it?” and Dean doesn’t cry, this time.


End file.
